Internal combustion engine



Dec. 1, 1942. D. M. WEIGEL INTERNAL COMBUSTION ENGINE 2 Sheets-Sheet l fig;

Filed April 30, 1941 YINIVENTOR.

DAN/1, Al. W576i! vMz 1942- D. M. WEIGEL INTERNAL COMBUSTION ENGINE Filed April 30, 1941 2 Sheets-Sheet 2 INVENTOR. .D/I/V/fl WE/GFZ Patented Dec. 1, 1942 2,303,966 INTERNAL COMBUSTION ENGINE Daniel Michael Weigel, Detroit, Mich.

Application April 30, 1941, Serial No. 391,156 In Great Britain May 2, 1940 8 Claims.

This invention relates to improvements in engines of the type disclosed in my prior Patent No. 2,220,926, dated November 11, 1940.

One object of the present invention is to simplify and improve engines of this type by forming the combustion chamber in a reciprocating sleeve which also controls various valve ports of the engine.

Other objects are to insure against leakage between the intake and outlet ports of the compressor by providing the reciprocating piston with a downwardly extending lip which is adapted to coact with one of the ports formed in the sleeve; to improve and simplify the valve arrangement for exhausting the spent gases from the power cylinder but controlling the exhaust solely by a poppet valve; and to reduce the number of valve ports and improve the operation of the engine by arranging the combustion chamber in the sleeve to function as a valve.

Other objects and advantages more or less ancillary to the foregoing and the manner in which all the various objects are realized will appear in the following description, which considered in connection with the accompanying drawings, sets forth the preferred embodiment of the invention.

Referring to the drawings:

Fig. l is a transverse view partly in section of a cylinder, piston and intercooler embodied in the present invention;

Fig. 2 is a diagrammatic view of the cylinder showing the position of the parts as determined by a 90 rotation of the crankshaft from the position shown in Fig. 1;

Fig. 3 is a diagrammatic view of the cylinder showing the position of the parts as determined by 180 rotation of the crankshaft;

Fig. 4 is a diagrammatic view of the cylinder showing the position of theparts as determined by 270 rotation of the crankshaft; and

Fig. 5 is a plan view of the interior surface of the slidable sleeve.

Referring to Fig. 1, there is shown a water jacketed cylinder l having secured to the lower end thereof a crankcase ll within which is journaled a crankshaft l2. Disposed within the crankcase ll there are timing gears l3, l4 and D which are arranged to drive a cam shaft H5 at the same rate of speed as the crankshaft l2.

A sleeve I1 is reciprocably mounted within the cylinder it]. A water jacketed cylinder head I8 secured to the upper end of the cylinder is provided with an inwardly projecting portion l9 adapted to define an annular recess for the reception of the upper end of the sleeve l1. Mounted in the portion IQ of the cylinder head are sealing rings .20 which are adapted to engage the inner surface of the sleeve H to seal the cylinder.

Secured to the lower end of the cylinder block is a tube 22 which has a cover 2| affixed to the end thereof which projects into the cylinder for closing the lower end of the cylinder. The peripheral surface of the tube 22 bears against the inner surface of the sleeve l'l while the inner surface of the tube serves as a guide for a cross head 24. The cross head 24 is connected to a crank 25 on the crankshaft 12 by a wrist pin and connecting rod 26. A piston rod 21 is secured to the cross head 24 and extends through an opening in the center of the cylinder cover 2|. A gland or the like 28 is carried by the cylinder cover 2! to seal the opening for the piston rod 21. Secured to the upper end of the piston rod 2i is a piston 29 having suitable packing rings 30 disposed therein for engagement with the inner surface of the sleeve ll.

Secured to the cam shaft I6 is a crank pin or eccentric 3i which has one end of a connecting rod 32 journaled thereon, the opposite end of which is connected to a laterally projecting arm 33 affixed to the sleeve H. The cam shaft I6 is also provided with a cam 34 engageable with a tappet 35 for operating a poppet exhaust valve 36, in the cylinder head, through a push-rod 31 and a rocker arm 38. The eccentric 3| for reciprocating the sleeve H is arranged to lead the crank pin 25 and piston 29 by about 90 so that when the piston is at its upper dead center, as illustrated in Fig. 1, the sleeve will have moved about half way through its downward travel. The cam 34 is designed to open the exhaust poppet valve 36 a short time prior to the piston reaching its lower dead center point and to close the poppet valve prior to the piston reaching its upper dead center. In accordance with the usual practice the exhaust valve may open from about 20 to 50 before the piston reaches the lower dead center.

The lower end of the sleeve H is provided with an intake port 39 which is adapted to register, during the upper half of the movement of the sleeve, with an intake port 40 which extends through the cylinder wall and leads to a suitable carburetor connection or other source of combustible mixture. The lower end of the sleeve is also formed with a port 4| arranged to register, through about the lower half of the movement of the sleeve, with a port 42 which is formedin.

the cylinder wall and connected to the inlet end of an intercooler 43. The upper end of the sleeve I1 is formed with an internal annular recess 44 which constitutes a combustion chamber. As shown in Fig. 5, the upper edge of the recess 44 is substantially sinuous and lands 45 project into the recess from the lower edge thereof so that suitable bearing surfaces are provided for engagement with the sealing rings 20 at every point throughout the vertical extent of the combustion chamber to prevent the rings 25 from expanding from their proper seats. It will be apparent that the combustion chamber may be shaped in various ways to provide the necessary space and at the same time maintain bearing surfaces for the rings at all times. A port 4'1! extends through the sleeve l! at a point near the upper edge of the recess 44 and is adapted to communicate with a port 58 formed in the cylinder wall and leading to the outlet end of the intercooler 43. Mounted within openings 5!! formed in the cylinder wall are spark plugs 55 which are adapted to communicate with the recess 44 through diametrically disposed openings 49 provided in the sleeve l1. Preferably the openings 49 are of such size as to maintain the spark plug openings 53 in communication with the recess 44 at all times.

The intercooler 43 is shown as constructed with an inlet header -52 connected with the port 42 and an outlet header 53 connected to the port 48. The headers 52 and 53 ar joined together by tubes 54 extending through a water jacket 55. A

water inlet connection 53 and outlet connection 51 are provided for circulating cooling water around the headers 5| and 52 and the tubes 54 in order to cool the gases contained therein.

Formed on the lower face of the piston 29 is a downwardly extending lip or projection 58 which is adapted to cooperate with a complementary slot 59 formed in the tube 22 for sealing the ports 4| and 42 against the passage of any of the gases from the intercooler 43 to the interior of the cylinder.

In operation the space between the piston and the cylinder cover 2| is alternately opened to the intake port 4i! leading to the carburetor or the like and to the port 42 connected to the intercooler. When the piston is at its upper dead center, as shown in Fig. 1, the sleeve I! is' approximately midway in its downward travel at I which time the port 39 has just moved out of communication with the intake port 48 while the port 4| in the sleeve is just about ready to register with the port 42. During the preceding upward or inward stroke of the piston the sleeve I? was moving through the inner or upper half of its travel so that the port 39 was in register with the port 40 and a charge of combustible mixture was inspired into the cylinder between the piston 29 and the cylindercover 2|.

As the piston moves on its downward or outward stroke from the position shown in Fig. 1, the sleeve continues its outward or downward movement in order to align the port 4| in the sleeve with the port 42 in the cylinder. During the previous downward or outward stroke of the piston the charge of combustible mixture inspired between the piston and the cylinder cover 2| is compressed in the intercooler 43. At the end of the outward stroke of the piston the sleeve i! has been moved to the position shown in Fig. 3 so that the port 42 leading to the intercooler is closed. As the piston approaches the end of its downward or outward stroke the lip 58 ismoved into the recess 59 formed in the tube 22 so as to into the intercooler.

seal the communication between the port 4| and the interior of the cylinder. As the piston reaches the end of its downward stroke the sleeve is approximately midway in its upward stroke so that the lip 58 coacts with the port 4! to prevent the admission of any of the compressed gases from the intercooler to the cylinder. When the sleeve l! is in approximately the mid position of its upward stroke the port 48 leading to the carburetor is again open to permit another charge to be inspired between the piston and the cylinder cover 2| upon the next inward stroke of the piston.

As will be explained in describing the opera tion of the power end of the cylinder the combustion chamber 44. is open to the outlet end of the intercooler once during each inward stroke of the piston. Thus on successive strokes of the piston the pressure in the intercooler 43 is built up until the weight of compressed mixture admitted to the combustion chamber is equal to the weight of mixture inspired below the piston on each inward stroke, at which time the intercooler may contain several inspired volumes of mixture compressed therein. Thus the ratio between the displacement volume on the under side or compression side of the piston to the volume of the combustion chamber is the compression ratio of the engine.

In the preferred form of the invention a substantial part of the heat of compression is removed from the compressed mixture by the circulating water or other cooling medium in the intercooler 43 so that the compression ratio may be 17 to 1 or more without raising excessively the temperature of the compressed mixture as would be done if the compression were carried out 'adiabatically. In order to attain such compression ratios without raising the temperature of the gas being compressed below the piston to a dangerous point before the gas reaches the intercooler, the port 6| in the sleeve is arranged to register with the port 42 leading to the intercooler immediately after the intake port 48 has been closed and near the beginning of the outward or compression stroke of the piston. As soon as the port 4| in the sleeve l1 registers with the port 42 the highly compressed, cooled gas in the intercooler expands into the cylinder, thereby raising the pressure of the newly inspired charge to a point near its maximum pressure without a corresponding rise in temperature. This is so since the gas expanding into the cylinder from the intercooler is cooled by such expansion in ubstantially the same amount as the newly inspired gas tends to become heated by its compression.

During the outward stroke of the piston, therefore, the gas contained in the combined volumes of the intercooler and the cylinder is compressed While this compressing acadiabatic since it is performed rapidly there is but a relatively slight rise in temperature of the entire body of the gas due to the relatively low compression ratio. All or any desired proportion of the heat so imparted tion is substantially to the compressed gas may be removed by the cirits innervalve 35* cation with the cylinder.

has closed and the sleeve I! has moved on its downward or outward travel so that the combustion chamber 44 which has been filled with a charge of compressed,cooled mixture from the intercooler is about ready to open, or has just opened, to the cylinder. Slightly before inner dead center the charge in the combustion chamber is fired by means of the spark plugs and the burning mixture expands into the power cylinder, forcing the piston outward or downward and turning the crankshaft. By reason of the fact that the exhaust valve 36 opens prior to the piston reaching its outer dead center the pressure in the combustion chamber is reduced substantiallyto atmospheric pressure before the sleeve valve again moves the combustion chamber out of communi- Thus thecombustion chamber contains spent gases at only about atmospheric pressure when the combustion chamber is again moved so that the port 41 and 48 register and permit'the combustion chamber to be again filled with compressed cooled gas from the intercooler.

The cycle of operations is illustrated by Figs.

1, 2, 3 and 4 which show the positions of the parts at each 90 of crankshaft rotation. In Figs. 2, 3 and 4, it will be understood that the eccentric for operating the sleeve valve has been shown on the opposite side of the cylinder from the cam for the sake of clearance although in practice it is only necessary to use one cam shaft for operating both the poppet valve and the sleeve, as illustrated in Fig. 1.

In carrying out the cycle of operations, the timing of the valves and ignition may be varied in accordance with the desired speed and other factors of the particular engine. A preferred timing is'substantially as follows: The movement of the sleeve H is approximately 90 ahead of the reciprocation of the piston, so that when the piston is at the end of its downward or outward stroke the sleeve has moved approximately half way through its upward or inward stroke. The

ports 39 and 4| in the sleeve H are so positioned with respect to their cooperating port 41 and 42 in the cylinder that there will be a short interval between the closing of ports 39 and 40 and the opening of ports 4| and 42. plished by having the port 39 remain communication with the port 40 through 160 of rotation of the crankshaft or movement of the piston and have the port 4| remain in registry with the port 42 through 180 movement of the piston.

As the piston starts on its upward stroke the sleeve and piston move approximately 10 before the inlet port 39 is brought into registry with the inlet port 40. These ports remain open to the admission of a new combustible mixture while the sleeve moves through approximately 160 or until it is about midway upon its downward or outward movement, at which time the inlet port is closed. The sleeve continues to move through approximately 10 prior to the opening of the outlet port 41 during which time the piston has reached the end of its inward stroke, so that, as the piston starts upon its downward stroke the newly admitted mixture of combustible gases is inter mingled with the gases flowing from the intercooler prior to the compressing and delivering of the intermingled gases to the intercooler.

After the piston has moved through approximately 45 of its upward or inward stroke the sleeve 11 moves the port 41 of the combustion chamber into registry with the port 48 of the intercooler to direct a charge of combustible mix- This may be accomture from the intercooler '43" to the combustion chamber 44. The port 41 is retained in communication with the port 48 for approximately of the upward or inward movement of the piston, or until the piston is about 45 from its top dead center. The combustion chamber 44 is retained in communication with the spark plugs 5| so that when the piston is approximately 25 from its top dead center position the combustible mixture is ignited, after which the continued movement of the sleeve moves the combustion chamber into communication with the cylinder just prior tothe piston reaching its top dead center. Approximately 45 prior to the piston reaching its lower dead center point the exahust poppet valve 36 is opened and remains open during the greater portion of the upward or inward stroke of the piston. The poppet valve 36 closes approximately 18 prior to the piston reaching its top dead center and just before the ignited combustible mixture is delivered from the combustion chamber to the cylinder. I

It will be seen that with this cycle of operation the combustible mixture is compressed'and cooled and the successive charges of the compressed, cooled mixture are burned and expanded adiabatically on the power stroke of the piston. In the preferred form the compression maybe substantially isothermal and the compression ratio may be maintained well above a ratio which in adiabatic compression would cause pre-ignition of the gas. Likewise the handling of the mixture through the compression cylinder and intercooler provides agitation and time for more complete atomization of the gas and a more uniform mixture. In addition, four swept out displacement periods of operation are performed in a single displacement volume upon a complete rotation of the crankshaft.

If desired, an automatic valve may be used in the port 42 leading to the inlet end of the intercocler to prevent the re-expansion of the compressed gas into the intercooler at the beginning of the compression stroke, provided the pressure of the cooled gas maintained in the intercooler is sufficiently low so that the automatic valve will'open on the compression stroke before the; newly inspired charge being compressed has been. raised to a dangerous temperature by the adiabatic compression. It will also be apparent that: manycom'pression arrangements other than that: illustrated might be used with the combustion: chamber carried in the sleeve, and likewise that; the general cycle referred to above may be c'ar-- ried out in engines having other forms of com-- bustion chambers, valves and the like",

Although the foregoing description is necessarily of a detailed character, in order that the invention may be completely set forth, it is to be understood that the specific terminology is not intended to be restrictive or confining, and that various rearrangements of parts and modifications of detail may be resorted towithout departing from the scope or spirit of the invention as herein claimed.

I claim:

1. An internal combustion engine having a cylinder, a sleeve reciprocable in the cylinder, a piston reciprocable in the sleeve, said sleeve having a recess formed therein constituting a combustion chamber and arranged to be opened alternately to a supply of combustible mixture under pressure, and to the cylinder, said sleeve also controlling ports on the underside of the piston arranged to open the cylinder automatically to a supply of combustible miXtule and 1 a i ter-- cQQler from which the compressed mixture is ad mitted to the combustion chamber.

An internal combustion engine comprising a. cylinder having a double acting reciprocating piston therein, an intercooler connected to the compression and power ends of said cylinder, a sleeve interposed between the piston and cylinder and adapted to reciprocate in timed relation with the piston, a plurality of ports in said sleeve coacting with ports in said cylinder to supply a combustible mixture to the intercooler, said sleeve provided with a recess constituting a combustion chamber arran ed for communication with the intercooler subsequent the closing of one of the ports in said cylinder.

An internal combustion engine comprising a cylinder having a sleeve slidably mounted therein, a reciprocating piston in said sleeve, in,- let and outlet ports in said sleeve arranged to communicate with complementary ports in the cylinder, said sleeve having a recess therein con stituting a ,combustion chamber arranged to communicate with the cylinder, an exhaust poppet valve in the cylinder, a downwardly extending lip onsaid piston adapted to seal the outlet port of the sleeve upon the opening of the poppet valve.

4. An internal combustion engine comprising a cylinder, a sleeve reciprocable in the cylinder, :1. piston reciprocable in the sleeve, said sleeve having a recess formed therein contituting a combustion chamber arranged to communicate with the power end of said piston, lands formed on said sleeve and projecting into the combustion chamber, sealing rings provided in the head of the cylinder contiguous the surface of the sleeve defining the combustion chamber, said lands engageable with the rings during the reciprocation of said sleeve to prevent displacement of said rings into said combustion chamber.

, 5. An internal combustion engine comprising a cylinder having a double acting reciprocating piston therein, an intercooler connected to the compression and power ends of said cylinder, a sleeve interposed between the piston and cylinder and adapted to reciprocate in timed relation with the piston, a combustion chamber, said chamber communicating with the intercooler and the power end of said piston during the reciprocation of said sleeve and an exhaust poppet valve in the power end of the cylinder.

6. An internal combustion engine having a cylinder, a sleeve having a cylindrical outer surface slidably engaged in the cylinder, said sleeve having a cylindrical inner surface, a piston reci oc bl mounted in -.said s e e a d s id bly earin o the inne sur ac th e f a d-sl e e h in a recess exte d n ou a d om the inn r sur a t e eo b n i el h ous the wall defined by said inner and outer surfaces and constituting a combustion chamber, and ean to ec ocat sa s e v a d ton ar-. ranged o n aid o b o cham e to a, incl supply and close the same to said cylinder, and alternately to open said combustion ch amher to said cylinder and close the same tq the ue s pp y- 7. An internal combustion engine having a cylinder, a cylinder head closing one end of said c der and ha in a iectinspo t n e ding into the cylinder and spaced from the wall thereoi, a sleeve havingan outer surface slidably engaging the cylinder and an inner surface slida y e a in s id p ojec n r n. o i n e head a p s o i r b v mount n. said sleeve, said sleeve being formed. with a recess p nin hr ugh he i ner sur a e he eo and constituting a combustion chamber, and-means for reciprocating said sleeve arranged to move aid mbu io c ambe int th s a e e n said cylinder and said projecting portion to close said combustion chamber from the cylinder and open the same to a supply of compressed gas, and arranged to move said combustion chamber into communication with said Cylinder beyond said projecting portion.

8. An internal combustion engine having a cylinder, a cylinder head closing one end of said cylinder and having a projecting portion extendi g into the the cylinder and spaced from the Wall thereof, a supply passage for compressed gas opening into the space between the cylinder wall and said projecting portion, a sleeve having an outer surface slidably engaging the cylinder and an inner surface slidably engaging said projecti is po o av i ton pr a m n e n said sleeve, saidsleeve being formed with a recess opening through the inner surface thereof, means f or reciprocating said sleeve arranged to move said sleeve into the space between said cylinder and said projecting Portion so as first to close communication between said combustion cham berand said cylinder and then opensaid combus: ti n chamber to said supply passage, saidmeans being arranged to move said combustion chamher in the opposite direction into communica-: tio Wi h' ai yli er, ai s e e ein arran ed to maintain said supply passage closed while said combustion chamber is in communication with said cylinder. r DANIEL M. WEIGEL. 

